MEXICO CITY — Gangsters may have claimed the lives of Maria Concepcion Vizarretea's three older brothers, but she doesn't know for sure, and her private agony is part of a larger drama that's unfolding across Mexico.
The brothers disappeared after a bus trip from Oaxaca state in Mexico's south to the northern border city of Matamoros to buy construction equipment. Vizarretea fears that they fell victim to violence by drug and criminal syndicates.
As the numbers of missing and dead mount in Mexico, thousands of families suffer the same uncertainty. Mexico has no centralized system to track and identify those who disappear. Hundreds of bodies pulled from clandestine mass graves remain unidentified for the most part, nameless victims of Mexico's ongoing carnage.
"We need to know who these people are," President Felipe Calderon told a gathering of the country's governors this week. "It is fundamental to know this. It doesn't matter whether they were young people recruited by cartels, abductees murdered by delinquents or victims of clashes between criminal groups or between criminals and the authorities."
The National Human Rights Commission said in April that 5,397 people had been reported missing since Calderon came to office in late 2006 and declared war on crime gangs. That doesn't include hundreds, if not thousands, of foreign migrants who've vanished while passing through Mexico for the United States.
The steady discovery of increasingly horrific mass killings — and the inability of authorities to identify them — has fueled the call to find better ways to track people who disappear. Of 193 bodies pulled from graves found in Tamaulipas state since April, only 17 have been identified. Mass graves in the northern city of Durango have given up some 250 bodies since mid-April. Mexican news media say that only three have been identified.
Under Mexico's federal system, it's the responsibility of the 31 states, the federal district and their individual coroners' offices to identify and dispose of the dead. Many keep registries but they aren't networked into a nationwide system.
"They just don't connect. They don't speak to each other," Dr. Morris Tidball-Binz, an Argentine forensic expert at the International Committee of the Red Cross, said in a telephone call from the humanitarian group's headquarters in Geneva.
Relatives of those who've disappeared say state officials often treat them with scorn as they follow the trails of loved ones across Mexico and inquire about their fates.
"The assumption of authorities in Mexico in general is that people who disappear were involved in criminal activities. It's a presumption of guilt, and one that state officials will openly express to family members of victims when they come to report cases," said Nik Steinberg, a Mexico researcher for Human Rights Watch, a New York-based advocacy group.
Vizarretea, 31, said her brothers were among 10 people from the Oaxaca town of San Pedro Pochutla who traveled to Matamoros, on the border with Texas, last July. They carried cash and were hoping to buy a used backhoe. After one of the men phoned his wife from Matamoros on July 14, they vanished.
Relatives sent a representative to Matamoros but the woman could find no information and returned quickly. Family members made repeated visits to Oaxaca state offices pleading for help.
Five months later, investigators arrived at the Vizarretea home to take saliva swabs and hair samples from her parents for DNA comparisons with bodies dug up in mass graves in Tamaulipas state.
At one point, officials said the men had been located in a prison in Morelos state, but that was false. Then they returned with a corpse, but the body wasn't one of their loved ones, who they now suspect are dead.
"We want to bury them in our town. But it has to be them. Don't bring us some corpse that isn't ours just so that we stop looking," Vizarretea said. "That's what they tried to do two months ago with a corpse that didn't belong to us."
Humanitarian experts said the disappearances were causing tremendous affliction.
"We know from experience worldwide that the suffering that such families go through is not only very deep but can last many, many years," said Tidball-Binz of the ICRC. "They have a right to know, and deserve to know, the whereabouts of their loved ones, and if dead, to recover the remains for proper burial and mourning."
The ICRC has played a backstage role in gathering state coroners and forensic specialists together to devise standards for postmortem data. Preliminary guidelines are being tested in several states, Tidball-Binz said.
Government inaction in identifying bodies and treating disappearances as serious crimes could spark even greater violence, rights monitors warn.
"The more that the state lags in investigating all these disappearances, the more it fosters a climate of lawlessness in which more of these crimes will take place," Steinberg said.
Events in Mexico seem to bear that out. Last August, an Ecuadorean survivor alerted authorities to a ranch where gunmen had executed 72 migrants in San Fernando, Tamaulipas state.
Then in early April, authorities discovered several mass graves around San Fernando that yielded scores of bodies, many of them migrants from other states whom gangsters had pulled off buses.
In mid-April, officials began unearthing the mass graves in Durango.
Early this week, Roman Catholic priest Alejandro Solalinde said witnesses told him that masked gunmen had abducted as many as 80 undocumented migrants, mostly Central American, from a train that was heading from Oaxaca to Veracruz on June 24.
The allegation set off alarms that the abductees might end up in still another mass grave.
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